Automotive design and manufacturing has included an increasing quantity of consumer and performance features. These features provide a range of information regarding vehicle performance and function. Wherein many of these systems were traditionally either accomplished manually or required a physical wire connection to vehicle computers, more systems within the vehicle now operate through wireless transmission.
A feature that provides considerable challenges involves the monitoring of vehicle tire pressure. Correct tire pressure is highly desirable as it impacts vehicle handling, fuel economy, tire wear, etc. In order to properly monitor tire pressure, systems are commonly mounted within the tire and attached to either the valve stem or the wheel rim. These systems include pressure sensors and wireless transmitters to transmit individual pressures to a central computer. As the sensor assemblies are mounted within the wheel during vehicle operations, these systems must be extremely robust. Tire impact, high rotational speeds, and quick momentum shifts must all be accommodated. Therefore it is highly desirable for the sensor assemblies to be designed for extreme conditions.
Although momentum based stressors are of considerable concern, so additionally are environmental stressors. Vehicle wheel assemblies often are exposed to considerable environmental changes. Water or other fluids may accumulate within the wheel during routine operations. When the wheel is at a twelve o'clock or six o'clock position, such accumulation may adversely effect the sensor assembly if such fluid is allowed to enter the pressure inlet port of the sensor assembly. The sensor element itself may be permanently damaged should such fluid be allowed to contact the electronics. Therefore, it is highly desirable to have a tire pressure monitor assembly that was extremely robust and was resistant to fluid intrusion. Such a monitoring assembly would increase lifespan and reduce warranty costs.